Roof structure form employing radial cables



Jan. 15, 1963 A G. E. M9Gu|RE 3,072,996

RooF STRUCTURE FORM EMPLOYING RADIAL CABLES Filed Sept. 4, 1959 "0V 8F761. ef 8 T n GERA/.o .Mssumf United States The present inventionrelates to a roof structure, and pertains more particularly to a roofstructure which can be used either to provide a form for a concrete roofslab, or which can of itself serve as alight weight or temporary rooffor a circular building.

The use of a circular building form is of considerable interest in mostarchitectural and building practice. In many small buildings, such as,for example, silos, the use of a circular wall form is almost universal,but in larger buildings such as houses, auditoriums and publicbuildings, the use of a circular form is sometimes desirable, but theatent provision of a suitable roof structure for such a circularbuilding frequently presents serious problems.

The present invention contemplates the provision of an improved andsimplified roof structure for a circular walled building.

The invention also provides a roof structure for a circular Walledbuilding wherein a plurality of roof panel supporting cables extendradially from a central member, the radially outward ends of the cablesbeing supported by external brackets on the circular wall of thebuilding, the central member being raised by means of a jack structureto place the cables under suitable tension, and roof panels aresupported on the cables.

A further object of the invention is to provide a roof form structurewherein a plurality of cables extend radially outwardly from a centralpost, passing through notches provided therefor in the circular wall ofa building upon which the roof is to be mounted, the outer ends of thecables being supported by brackets projecting outwardly beyond theirrespective wall notches, the central post being axially extensible toplace the cables `under roof deck supporting tension.

These, and other objects and advantages of the invention, will beapparent from the following description and the accompanying drawings,wherein:

FIG. 1 is a plan view of a circular walled building having a roofstructure embodying the present invention, a cement slab roof beingshown in various stages of completion thereon.

FIG. 2 is a sectional view taken along line 2 2 of FIG. 1'.

FIG. 3 is an enlarged, fragmentary, sectional view taken along line 3-3of FIG. l.

FIG. 4 is an enlarged fragmentary, sectional view taken along line 4-4of FIG. 1. l l

Briey, a roof structure A embodying the invention comprises a centralcable anchor member 10 mounted at the top of an extensible center post11 which is provided with screw means 12 for extending the post axially.A plurality of cables 13 extend radially from the central member 10, oneto the outer end of each of a plurality of brackets 14 which areremovably mounted, in symmetrically spaced relation, to extend radiallyoutwardly near the upper end of a cylindrical wall structure B. A notch15 is provided in the Wall B radially inwardly of each bracket 14 topermit an associated' cable 13 to be withdrawn inwardly therethroughafter a concrete roof slab C has been completed.

When the cables 13 are all led from their point of connection to thecentral member 10, through their respective notches 15, and are securedto their respective brackets 14, the center post 11 is extended axiallyby means of the screw 12 and thereby place the cables 13 under suicienttension to support segmental panels or form boards 17 and 18, which aresupported on the cables 13, and are secured against displacement thereonby suitable interconnections 16.

Structural steel, not shown, may be embedded in the concrete slab C asthe latter is deposited on the panels 17 and 18.

Referring to the drawings in detail, the illustrated central member 10is of steel plate, and is in the form of a cone with its wall slopecorresponding to that of the roof structure A to be constructed thereon.The central member 10 is provided with a plurality of securing eyes 19welded marginally thereto, and to which an equal plurality `of thecables 13 may be connected, one to each of said eyes. The specific formof the central member'l and cable attaching means employed are, however,capable of substantial variation by one familiar with the art.

The cables 13 are of uniform length, and the diameter of the cablesemployed depends upon the stresses to which vthey will be subjected inuse. For example, for a silo having an 8 foot radius, and with thenumber of segments illustrated, steel cables of 1A inch diameter wouldbe adequate. For larger structures the size of the cables wouldnecessarily have to be increased. A suitable cable size for any proposedroof structure can be easily selected by means of conventionalengineering calculations.

'I'he center post 11 comprises an upper portion 11a, which may be ofsteel pipe or tubing of suicient strength to withstand the compressionstresses to which it is subjected in use. As illustrated this pipe 11ais mounted on the jack screw 12 adapted to be actuated by a turninghandle 12a. A cable 13 is secured, as by means of a conyentional eyesplice 20, to each of the mounting eyes 19 provided therefor on thecentral member 10. The outer end of each of the cables 13 is alsoprovided with a similar eye splice 20 for fitting over a hook 21provided therefor on the outer end of its respective bracket 14.

A bracket 14 is provided for each of the cables 13, and, as illustrated,comprises a structural steel member having a right angle bend 22therein. An upright arm 23 of each bracket 14 is secured to the outerface of the circular building wall B by bolts 24, the heads 24a of whichare embedded in the concrete of the wall during its construction. Thethreaded ends of these bolts 24 project outwardly from the wall B, andthe upright arm 23 of each bracket 14 is provided with holes therein toreceive these bolts. Nuts 25 threaded onto the projecting ends of thebolts 24 secure the brackets 14 rmly to the wall B. Each bracket 14 alsohas a laterally extending arm 27 which extends outwardly at right anglesto the wall B and is provided with the hook Z1 on its outer end to litinto au eye splice 20 of its respective cable 13.

A plurality of the notches 15 are provided in the upper edge of the wallB during its construction, each notch 15 being located radially inwardlyof one of the brackets 14 to receive an associated cable 13 therein, andalso to permit the cables 13 to be withdrawn through these notches aftera concrete roof slab C has been completed.

Where the invention is to be used to provide a form for a concrete roofslab C, the radially inner set of segmental panels 17 is provided, eachpanel 17 extending from the circular Wall B inwardly to a point adjacentthe axial center ofthe wall B. A radially outer set of panels 18 also isprovided, each outer panel 18 extending from the outer edge of the wallB outwardly to the ends of the cables 13. Each panel 17 and 18 Visadapted to cover the segmental space between a pair of adjacent Y cables13, and, complementarily with each other, the

entire roof area.

Any4 suitable form material may be used for the panels 17 and 18, suchas, for example, sheet metal, plywood, hard pressed water proof pulpboard or other suitable form `building material; The illustrated panels17 and 18 that knownras a Gunite gun.

may be of sheet metal, and each has an upstanding bead y the art, andsuch other types of interconnections may be substituted 4for the bead'and flange type illustrated and described specifically herein. A smallplate or cover 28, which may be of sheet metal, is provided over each ofthe notches to prevent therlatter. from lfilling with concrete duringthe application of the roof slab C.

The outer end 17a of each Vinner panel 17, and the inner end 18a of eachouter panel 18 is curved to conform to the curvature of the wall B. Aretaining flange 30 is provided on Vthe outer end of each of the outerVpanels 18' to' retain the concrete of the slab C and to square up theouter edge of said slab. This flange 30, as illustrated, comprises awooden strip secured transversely across the outer end of each outerpanel 18 and extending the full width thereof.

In practicing the present invention, after the wall B hasV beenconstructed with the notches 15'therein vfor the required number ofcables 13"to be employed, and the bolts 24 for supporting the brackets14 are embedded therein as mentioned previously herein, Ithe brackets 14are applied to the wall B and are secured thereto by means of the nuts25 threaded onto the bolts 24. The center Vpost 11 inkits retractedcondition indicated by broken lines in FIG. 2 is then'set up axially ofthe wall B, and with'the central member 10 mounted thereon.

rWith thev center post in its thus retracted condition, Ysufficientslack will be available in the cables 13 to permit the spliced eye 20 inthe outer end Vof each cable 13 to be looped over. ahook 21 providedtherefor on the outer endv of each bracket 14. After thecables 13'havebeen thus attached-to the brackets 14, the center post 10 is extendedaxially by turning the Iscrew 12 vto place the cables 13 under'sufcienttension to`support thel loadto which they will be subjected.

Assuming that a concrete roof slab C is to be employed,

the form p`anels'17k and 18 are then fittedl onto the portions of thecables 13 inwardly of the wall B, Vand said panels are interconnectedwith each otherby placing the hooked flange 16b of each panel over thesmaller bead 16a of the panel adjacent thereto. The outer panels 18 aresimilarly mounted on the outer reaches of the cables 13 from the wall Boutwardly, and are similarly interconnected with eachother.

' The vconcrete C is then applied to the panels as illustrated in FIGS.l and 2, either by pouring, or by application with. a pressure spraydevice such as, for example, Reinforcing steel (not shown) may beembodied in the concrete slab C in a conventional-manner duringconstruction of the slab if desired.

' Afterv the concrete roof slab C has been completed, andhas beenallowed to age suicienty to attain adequate strength, the center post 11is retracted by means of the screw 12Ato its broken Vline position ofFIG. 2 to thereby Slack ofI' the cables 13. The brackets 14 are thenremoved from the wall B, the cables 13 are withdrawn in-kr .in the eventthat no concrete roof slab C is to be employed, it is preferred thatinstead of using separate inner and outer panels 17 and 18 in ordertoexpose the upper 4 edge of the wall B, that continuous panels 32( FIG.l) be employed, extending from the axial center of the wall B .to theouter ends of the cables 13. When such full length panels are employedit will obviously not be necessary to provide the covers 'ZISfor thenotches A15, since no concrete roof slab is tobte applied thereon.

The inventionprovide's a simple. inexpensive and easily erectedI roofstructure, and one which may either serve as a roof of itself, or whichprovides a form for the making of a concrete slab roof. Also, while theinvention has been described for use with a circular walled building itis obvious that it may be used with a polygonal walled building havingany desired number of sides.

While I have illustrated and described a preferred emf bodiment of thepresent invention, it will be understood, however, that various changesand modications may be madein the details thereof withoutV departingfrom the scope of the. invention as set forth in the appended claims.

Having thus described the invention, what I claim as new and desire toprotect by Letters Patent is dened in the following claims.

I claim:

l. A roof form for a building having a floor and a wall encircling saiddoor, said roof form comprising a central member, a plurality of roofpanel supporting cables attached at their inner ends to said centralmember, a plurality of brackets, one for each of the cables, removablyattached to the outer face of such wall at spaced intervals therearoundand adjacent the upper end thereof, such wall havingv a notch thereinradially inwardly of each of the brackets, means on the outer end ofeach bracket for attachingone of the cables thereto, thereby to supportthe cables in radial extensionfrom the central member and through thenotches inwardly of their respective brackets, and axially extensiblecenter post mounted upright and extending between the central member anda oor of such building, means for axially extending the center post toelevate the center member and thereby place under tension the cablesextending from the central member to the brackets, a first plurality ofsegmental roof panels, each of a size to ll'the space between eachadjacent pair of said cables inwardly of thewall, and means forsupportving said panels in complementary relation, on the cables, theouter ends ofsaid panels abutting such wall, and a second set of panelseach of a size to ll the space between adjacent cables. exteriorly ofthe wall, whereby when a concrete roof slab is formed on top of thepanels and of the wall, after the roof slab has set, upon removing l thecentral member the cables are slackened, thereby freeing the panels fordownward removal from such slab.

2. A roof form for a building having a door and a Wall encircling saidoor, said roof form comprising a central member, a plurality of roofpanel supporting cables attached at their inner ends to said centralmembers a plurality of brackets, one for each of the cables, removablyattached to the outer face of such wall at spaced intervals therearoundand adjacent the upper end thereof, such wall having a notch thereinradially inwardly of each Vof the brackets, means on the outer end ofeach bracket for attaching one of the cables thereto, thereby to supportthe cables in radial extension from the central member and through thenotches inwardly of their respective brackets, an axiallyextensiblecenter post mounted upright and extending between the central member anda floor of such building,rmeans for axially vextending the center postto elevate the center member and thereby place under tension the cablesextending from the central member to the brackets, a plurality ofsegmental roof panels, each of a size to fill the space between eachadjacent pair of Vsaid cables, means for supporting said panels on thecables between which they are mounted toV prevent displacement thereofwhen said panels are supported on the cables in space lling relation theouter ends of saidV panels abutting such wall, and terminating inwardlythereof, whereby when a concrete roof slab is;

formed on top of the panels and of the wall, after the roof slab hasset, upon retracting the center post to slacken the cables the panelsare removable downwardly from the slab.

3. A roof -form for a building having a oor and a wall encircling saidoor, said roof form comprising a central member, a plurality of roofpanel supporting cables attached at their inner ends to said centralmember, a plurality of brackets, one for each of the cables, removablyattached to the outer face of such wall is symmetrical, spaced relationtherearound and adjacent the upper end thereof, such wall having a notchtherein radially inwardly of each of the brackets, means on the outerend of each bracket for attaching one of the cables thereto, thereby tosupport the cables in radial extension from the central member andthrough'the notches inwardly of their respective brackets, an axiallyextensible center post mounted upright and extending between the centralmem'- ber and a tloor of such building, means for axially extending thecenter post to elevate the center member and thereby place under tensionthe cables extending from the central member to the brackets, aplurality of segmental roof panels extending from the wall, inwardly,each of a size to till the space between a pair of adjacent ones of saidcables, and means for attaching adjacent panels to each other to preventdisplacement thereof when said panels are supported on the cables inspace filling relation, thereby leaving the top of the wall exposed, anda' cover plate adapted to mount over each of said notches for excludingconcrete therefrom when applying the concrete roof slab, said panels andthe exposed top of the wall comprising a form for the casting of aconcrete roof slab thereon, the cables being removable through thenotches after such roof slab has set for removing support from thepanels to free the latter for removal, and the panels being therebyfreed for downward removal from the slab.

'14. A roof form for a building having a oor and a wall encircling saidoor, said roof form comprising a plurality of brackets, removablyattached to the outer face of such wall at spaced intervals therearoundand adjacent the upper end thereof, such wall having a notch thereinradially inwardly of each of the brackets, means on the outer end ofeach bracket for attaching a cable thereto, each of the cables beingbrought inwardly within the wall through the notch inwardly of thebracket lto which said each cable is attached, an axially extensiblecenter post mounted upright substantially centrally of the floor of,such building, means for attaching the inner end of each cable to anupper portion of the center post, means for axially extending the centerpost to elevate the inner cable ends above their points of attachment tothe brackets and thereby place under tension said cables,

6 a plurality of segmental roof panels, each of a size to till the spacebetween a pair of adjacent ones of -said cables, and extending outwardlyto such wall, means for supporting said panels, in complementaryrelation, on the cables, thereby to ll the spaces between the cables andextending outwardly to the wall and thus provide a roof form for thecasting of a concrete roof slab thereon.

5. A roof form for a building having a floor and a wall encircling saidfloor, said roof form comprising a plurality of brackets, removablyattached to the outer face of such wall at spaced intervals therearoundand adjacent the upper end thereof, su'ch wall having a cable receivingnotch therein radially inwardly of each of the brackets, means on theouter end of each bracket for attaching a cable thereto, each of thecables being brought inwardly within the wall through the notch inwardlyof the bracket to which said each cable is attached, an axiallyextensible -center post mounted upright substantially centrally of theHoor of such building, means for attaching the inner end of each cableto an upper portion of the center post, means for axially extending thecenter post to elevate the inner cable ends above their points of vattachment to the brackets and thereby place under tension said cables,a first plurality of segmental roof panels,

each of a size to fill the space between a pair of adjacent ones of saidcables and to extend outwardly to such wall, means for supporting saidpanels in complementary relation, on the cables and abutting such wallthereby to ll the spaces between the cables, a second plurality ofsegmental panels supported in complementary relation between adjacentcables exteriorly of and abuting such wall, whereby the upper portion ofsuch wall is exposed between the two pluralities of panels, and wherebya concrete roof slab cast on said panels as a form is in intimate bondedrelation with such exposed wall portion, whereby, after the roof slabhas set upon retracting the center post the cables are thereby slackenedand the panels are released for downward removal from the roof slab, andupon release of the outer ends of the cables from their brackets thecables are freed for drawing inwardly through the openings provided bythe covered notches.

References Cited in the tile of this patent UNITED STATES PATENTS988,731 Naylor Apr. 4, 1911 998,575 Hanson July 18, 1911 1,161,115 DuinNov. 23, 1915 2,670,818 Hacker Mar. 2, 1954 v2,804,028 Wiggins Aug. 27,1957 OTHER REFERENCES Architectural Record,'September 1956, pages211-216.

1. A ROOF FORM FOR A BUILDING HAVING A FLOOR AND A WALL ENCIRCLING SAIDFLOOR, SAID ROOF FORM COMPRISING A CENTRAL MEMBER, A PLURALITY OF ROOFPANEL SUPPORTING CABLES ATTACHED AT THEIR INNER ENDS TO SAID CENTRALMEMBER, A PLURALITY OF BRACKETS, ONE FOR EACH OF THE CABLES, REMOVABLYATTACHED TO THE OUTER FACE OF SUCH WALL AT SPACED INTERVALS THEREAROUNDAND ADJACENT THE UPPER END THEREOF, SUCH WALL HAVING A NOTCH THEREINRADIALLY INWARDLY OF EACH OF THE BRACKETS, MEANS ON THE OUTER END OFEACH BRACKET FOR ATTACHING ONE OF THE CABLES THERETO, THEREBY TO SUPPORTTHE CABLES IN RADIAL EXTENSION FROM THE CENTRAL MEMBER AND THROUGH THENOTCHES INWARDLY OF THEIR RESPECTIVE BRACKETS, AND AXIALLY EXTENSIBLECENTER POST MOUNTED UPRIGHT AND EXTENDING BETWEEN THE CENTRAL MEMBER ANDA FLOOR OF SUCH BUILDING, MEANS FOR AXIALLY EXTENDING THE CENTER POST TOELEVATE THE CENTER MEMBER AND THEREBY PLACE UNDER TENSION THE CABLESEXTENDING FROM THE CENTRAL MEMBER TO THE BRACKETS, A FIRST PLURALITY OFSEGMENTAL ROOF PANELS, EACH OF A SIZE TO FILL THE SPACE BETWEEN EACHADJACENT PAIR OF SAID CABLES INWARDLY OF THE WALL, AND MEANS FORSUPPORTING SAID PANELS IN COMPLEMENTARY RELATION, ON THE CABLES, THEOUTER ENDS OF SAID PANELS ABUTTING SUCH WALL, AND A SECOND SET OF PANELSEACH OF A SIZE TO FILL THE SPACE BETWEEN ADJACENT CABLES EXTERIORLY OFTHE WALL, WHEREBY WHEN A CONCRETE ROOF SLAB IS FORMED ON TOP OF THEPANELS AND OF THE WALL, AFTER THE ROOF SLAB HAS SET, UPON REMOVING THECENTRAL MEMBER THE CABLES ARE SLACKENED, THEREBY FREEING THE PANELS FORDOWNWARD REMOVAL FROM SUCH SLAB.